LAS VEGAS — When Adreian Payne was 15 years old, he realized he needed a summer job. He was, after all, a teenager, and Payne heard the same siren song of commerce that appeals to adolescents everywhere.

“I wanted to be able to buy myself something,” Payne recalls. “I wanted to go to the mall with my friends and stuff like that.”

And so Payne, who grew up in Dayton, Ohio, went out and got a job. As a janitor at his own middle school.

To Payne, it was a great gig.

“I swept, took gum off of the desks, mopped. It wasn’t bad, because I knew everybody there at my school, and it was the summer so there wasn’t anybody there. But I knew the janitor, I knew the lunch lady, all the staff. It was kind of fun. Being young I played around sometimes, but it was fun.”

Once he saved up enough money, Payne went to the mall and bought a pair of shoes. These days, as the recent first round pick of the Atlanta Hawks, with the requisite rookie scale contract, Payne’s shopping horizons have broadened a bit: “I’m looking for an apartment right now, actually. That will probably be the next thing I get.”

Payne spent the past week in Las Vegas with the Atlanta Hawks at the Samsung NBA Summer League exhibiting the drive and skill that made the Hawks interested in him to begin with. As a four-year player for coach Tom Izzo at Michigan State, the 6-foot-10 Payne developed into a deft outside shooter, knocking down 3-pointers at a 42 percent rate as a senior. That combination of size and shooting ability should fit perfectly into the spread-and-shoot system the Hawks implemented last season under first-year head coach Mike Budenholzer.

“Being able to shoot the ball can translate to anything, any level,” Adreian said. “But [the NBA game is] a lot different, the speed of the game, and the players are more athletic. So it’s just a matter of you just getting more comfortable out there, trying to find the pace of the game so your shots still come and you’re in rhythm, still. So I’m just trying to get my shot off quicker but not in a rush. But just quicker, more efficient, less movement.”

Payne helped lead the Hawks’ summer squad to a 2-3 record in the round-robin format, and played 28 minutes today in the Hawks’ 78-71 elimination round loss to the Houston Rockets. Payne finished with 11 points but struggled from the field, finishing 4-for-15, including 1-8 on three pointers.

“They were telling me to get my shots, try to slow myself down, run the offense and let them come. They was coming, they just wasn’t falling,” Payne said with a laugh.

Hawks assistant coach Darvin Ham coached the Hawks summer league squad, and saw plenty to like from Payne.

“It’s one of those situations where you always love the fact you have to tell a guy to slow down as opposed to pick it up. He just needs to know how to be quick but not in a hurry,” said Ham. And then, to emphasize the point, he repeated it quickly and in a hurry: “Quick but not in a hurry.

“He gets going and he’s going full speed and that’s normal for guys coming out of college,” Ham said. “They want to do everything a thousand percent, at a hundred miles an hour, and you can’t fault him for that. He’s from a heckuva program and Coach Iz[zo] did a great job with him. We’re just going to try to refine him a little bit and teach him how to play with a change of pace, so to speak.”

Coming into today’s loss, Payne averaged 12.8 ppg on 40 percent shooting from the field in Atlanta’s five previous games. Ham said the Hawks know he can get his shot going.

“His shooting element is there,” said Ham, “the defensive element is there, making athletic plays, we just gotta get him to stop fouling so much.”

Is that easier said than done with rookies?

“Oh, absolutely,” Ham continued. “Because in college, they actually play a lot more physical than we do in the NBA. At the NBA level, the big key is not to impede progress, so referees are a little more ticky-tacky with how they call fouls as opposed to in the college game, where you can get into guys and put your forearm into ‘em when they face up and all of that. So it’ll take some time, but he’s a smart kid, a smart player, he’ll make the proper adjustments.”

One adjustment Payne has made thus far has been trying to add shotblocking to his defensive repertoire, something he says he wasn’t able to display at Michigan State.

“[Coach Izzo] wanted me to stay on the floor — I was getting in foul trouble. So the rules here are a lot different than they are in college — you have verticality here, in college you don’t. So it’s a lot different.”

Accordingly, another part of Payne’s adjustment has been studying tape of the NBA game to increase his familiarity with the league. While at Michigan State, he said, NBA games weren’t often on his TV — “I watched a lot of college games.” Video games were no help either — “I suck at 2K.”

“I’ve been watching a lot more NBA now, and I love watching it,” Payne said. “Now that I’m here in the league I’ve been watching a lot more film, been watching film with Coach Ham, and just trying to get better.”